fixed case where modifying a series of reservations

reserve.series.inc

@@ -124,7 +124,7 @@ function reserve_reserve_reservation_update($entity) {
   $rid = $entity->reservable_id->getString();
   $rtype = $entity->reservable_content_type->getString();
   $ebundle = $rtype . '.' . \Drupal::entityTypeManager()
-    ->getStorage($rtype)->load($id)->bundle();
+    ->getStorage($rtype)->load($rid)->bundle();
   $private = $entity->reservation_private->getString();
 
   // grab all reservations in this series except the one being submitted